Design rules to scale-up magnetic screens made of bulk superconductors and closed-loop coated conductors: modelling and experiments

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F25%3A43932900" target="_blank" >RIV/60461373:22310/25:43932900 - isvavai.cz</a>

Result on the web

<a href="https://iopscience.iop.org/article/10.1088/1361-6668/adaaa7/meta" target="_blank" >https://iopscience.iop.org/article/10.1088/1361-6668/adaaa7/meta</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1361-6668/adaaa7" target="_blank" >10.1088/1361-6668/adaaa7</a>

Result language

angličtina

Original language name

Design rules to scale-up magnetic screens made of bulk superconductors and closed-loop coated conductors: modelling and experiments

Original language description

Hybrid magnetic screens combining a disk-shaped high-temperature superconducting bulk with closed-loop coated conductors have been recently demonstrated to significantly overcome the screening properties of a single bulk. The purpose of the present work is to investigate how to scale up these hybrid screens, i.e. further increase the field attenuation and widen efficiently the screened region using more closed-loop coated conductors. First of all, an axisymmetric finite element model using the Gmsh and GetDP environments with the formulation is implemented and used to study the influence of physical and geometrical parameters of the screens. The results show that the low-field screening factor SF and the screened surface area are strongly dependent on the geometry while having large materials is mandatory to maintain the screening properties up to high fields. An important design rule is that the spacing between the concentric loops should be sufficiently small, which we explain physically by analysing the different paths followed by the flux lines. Then, experiments are carried out in liquid nitrogen (77 K) with GdBa2Cu3O7 samples. Mapping the three components of the flux density above the screens subjected to an inhomogeneous applied field gives the following key results. First, the combination of the bulk with four loops spaced as recommended by the numerical model allows the screened surface area (SF) to be multiplied by with respect to the bulk alone. Second, reducing the asymmetry of the practical structure by flipping over some of the loops is highly beneficial for improving the screening properties: the maximum SF at 5.7 mm the bulk is measured to be multiplied by 1.6 without any additional superconductor. Importantly, the design rules obtained from both the numerical model and the experiments can be further extended and applied to various geometries or sizes of hybrid superconducting screens.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Project

<a href="/en/project/GA24-10171S" target="_blank" >GA24-10171S: Melt-assisted growth of defect-free single-domain REBCO crystals</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2025

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

SUPERCONDUCTOR SCIENCE &amp; TECHNOLOGY

ISSN

0953-2048

e-ISSN

1361-6668

Volume of the periodical

38

Issue of the periodical within the volume

2

Country of publishing house

GB - UNITED KINGDOM

Number of pages

11

Pages from-to

nestránkováno

UT code for WoS article

001405218300001

EID of the result in the Scopus database

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